Pumping system for hydrostatic apparatus.



J. H. CLARK. PUMPING SYSTEM FOR HYDRQSTATIG APPARATUS.

APPLIOATION FILED SEPT. 3,1904.

Patented May I irl/1% i/ I y I H Fig.2.

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UNITED STATES PATENT OFFICE.

JOHN H. CLARK, OF SGHENEGTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY,

' A CORPORATION, OF NEW YORK.

PUMPING SYSTEM FOR HYDROSTATIO APPARATUS.

Specification of Letters Patent.

Patented May 4, 1909.

Application filed September 3, 1904. Serial No. 223,196.

' To all whom it may concern:

Be it known that I, JOHN H. CLARK, a citizen of the United States, residing at Scheneccounty of Schenectady, State of New York, have invented certain new and useful Improvements in Pumpin Systems for Hydrostatic Apparatus, of w iich the following is a specification.

The resent invention relates to hydrostaticall -actuated devices such as elevators, cranes, hoists, etc., and more particularly to the means for storing, subjecting to pressure and delivering the water or other liquid to the working cylinder of the device, and the object of the invention is to provide simple and highly efficient means of this character so constructed and arranged as to conserve to the fullest extent the potential energy of the descending loads and without producing excessive strains in the operative parts.

In carrying out my invention I provide an accumulator consisting of a hermeticallysealed tank of suflicient size to contain all the liquid used in the operation of the hydro.- statically-actuated device or devices and a considerable amount of air or other elastic medium, and between theaccumulator and each of the working cylinders of the devices I connect a um and a controlling valve so arranged t iat t 1e water passes'through the pump in the same direction both when passing from the accumulator to raise the lifting fromthe accumulator to raise the plunger Without subjecting the pump and its actuating mechanism to the great stresses incident to other forms of hydrostatic actuating devices.

' The invention will be stood u tailed more readily underon reference to the following deescription and the accompanying cation,

in whic Figure 1 shows in part side elevation and part section an arrangement of accumulator, pump, valve and-connections to an elevator cylinder embodying one form ofwmy invention; Fig. 2 is a lan of the same; and Fig. 3 is a lan in outline of the same arrangement in w iich a plurality of elevators are supplied from a common accumulator.

The accumulator which is shown in the form of a vertical cylindrical tank 1 and sealed air-tight is connected near its lower end by a main supply pi e '2 with the lower end of a valve chest 3 w ichis' in turn connected to the elevator cylinder 4. The valve chest 3 is provided with two passage ways 5 and 6 which are respectively connected with the suction p1pe 7 and the discharge pipe 8 of a centrifugal pump 9 and has a contra valve chamber 10 extending vertically therethrough connecting at its lower end with the main supply pipe 2 and with the ports 11 to the suction pipe 7, 12 to the elevator connection, and 13 to the discharge pipe 8 leadin from the sides thereof. Near the upper an of. the valve chamber 10 is an opening 14 connected by a bent by-pass pipe 15 to'the main supply pipe 2, and at its end is a stuffing box 16 through which passes the valve rod 17 on which are two valves 18 and 19. The pump 9 is shown connected to an electric motor 20, but it is, of course, ap arent that any suitable driving means may e employed.

When a number of elevators are located in the same building they may be connected to a single accumulator as shown in Fig. 3 by branch supply pipes 2\ leading from a main supply pipe 2 which is alone connected to accumulator, or they may be severally c011- n ected directly to accumulator if found more convenient.

The operation of the device shown is substantially as follows: When it is desired to raise the elevator the valve rod 17 is raised from the position shown in Fig. 1 so that valve 18 clears the lower seat of thedischarge port 13, and valve 19 clears the lower seat of port 11 and a channel for the water in the tank 1 is opened through supply pipe 2,'po rt 11 passage 5, suction pipe 7, pump 9, dlscharge pipe 8 passage 6 port 13 port 12 to. the elevator dylinder 4, the pressure on the v opposite ends of the valves being equalized or balanced through the by-pass pipe 15. When it is desired to stop the elevator the valves 18, 19 are moved downward into the osition'shown in Fig. 1 when valve 19 covers 0th seats of the suction port 11 and valve 18 from the elevator cylin covers the lower seat of port 13 so that no. exit is open to the water in the elevator cyl-. inder and no passage remains open to the out reversal operates in conjunction with the of the elevator, the maximum strains thrown' exhaust pipssurelof the water from the elevator cy' der to raise the pressure in the tank so that the only work imposed upon the pum is that necessary to overcome the preponuerance of the load over the tank pressure in going up and the preponderance of the tank (pressure over the load in coming down, an as Its effort is expended in the same direction throughout both movements upon the pump and its drivin means are only one-half as great as int e ordinary forms of hydraulically actuated elevator,

devices.

' I do not desire to restrict nyself to the articular form or arrangement of parts erem descrlbed and shown; since it 1s apceases parent that they may be changed and modied without departing from m invention.

What I claimas new and esire to secure by Letters Patent of the United States, is:-

1. The combination with a hydrostatic device and a pressure tank each having a passage way for the pressure fluid, of a valve chest having "connections at both ends with the passageway of the tank, and a central port connected to the passage way of the hydrostatic device, a unidirectional centrifugal pump having suction and discharge passa es connected to'intermediate ports in said va ve chest, and two valves in said chest in operative relation to said intermediate ports.

2. The combination with a hydrostatic device and a pressure tank each having a sin le passa e way for the pressure fluid, of a va ve chest having both its ends connected to the.

tank (passage way and a central port connecte to the passage way of the hydrostatic device, a unidirectional centrifugal pump having suction and discharge passages directly connected to orts in the valve chest on opposite sides 0 the central ort, and valves-for closing either or both of t 1e pump ports.

In witness whereof I have hereunto set my hand this 20th day of Au ust, 1904.

- JofiN H. CLARK.

Witnesses:

BENJAMIN B..HULL,

HELEN ORFORD. 

